Signal receiving system



u All@ l5, 1933 .H. J. J. M. DE R. DE BELLEsclzE 1,922,281-

SIGNAL REGEIVING SYSTEM F'l 24, 1932 4 She 't -She t 1 i *l* 1QQLEQ-:-g-l 66s e A A f1 v A q1 v -vS' Y Aug- 15, 1933 H. J. J. M. DE R.DE BELLI-:seize 1,922,282

S IGNAL RECEIVING SYSTEM Filed Feb. 24 1952 4 Sheets-Sheet 2 E ig. a14g/J E 30 HITIF @GMW- @Mv Muir l H. J. J. M. m w. ma mmmsclz 1,922,232

SIGNAL RECEIVING SYSTEM Filed F'eb. 24, 1932 4 SheeBS-Sheel 3V QQMAM,

AUS- 15, 1933. H. 1. J. M. ne: R. DE BELLEsclzE 1,922,282

' SIGNAL RECEIVING SYSTEM Filed Feb. 24, 1952 4 Sheets-Sheet 4 PatentedAug.7 l15, 1933 SIGNAL RECEIVING SYSTEM Henri Jean Joseph Marie deRegnauld de Bellescize, Neuilly-sur-Seine, France Application February24, 1932, Serial No. 594,885, and in France April 29, 1931 1 5 claims.

My invention relates broadly to the reception of transmitted signalswithout a carrier wave or carrier current, and more speciii'cally toasignaling system in which signals are transmitted 5 by means of aperiodic current whose phase may alternately shift in opposition.

One of the objects of my invention is to provide a communication systemoperating without a carrier wave or carrier current.-

Another object of my invention is to provide a system of signalingcircuits adapted for opera.-V tion either by line wire or by spacedradio` for the selective transmission oi' signals without a carrierwave.

Still another object oi' my invention is to provide a selectivetransmission and receiving system for electrical signals in which thesignaling energy is constituted by a periodic current whose' phasealternately shifts in opposition.

A further object of my invention is to provide an arrangement of signalreceiving circuit in which means are provided at the receiver forimpressing energy upon a detector in alternate opposed phase undercontrol of incoming signaling current for the selective operation of asignal indica-tor. A

A still further object of` my invention is to provide a selectivecircuit forthe reception of signaling energyY in which separate meansare 30 provided for increasing the frequency of the incoming signalingenergy and the frequency oi' a localV oscillator and deriving auxiliarycurrents which are mutually modulated for actuating a synchronizingsystem.

Another object of my invention is to provide a signal receiving circuitincluding a local oscillator, a detector and a signal indicator actuatedby the detector with means for combining in the said detector the signaloscillation with an oscillation of the local generator, and impressingthe current derived from the combination of these oscillations insuccessively opposite phase relations upon the detector for selectivelyoperating said indicator. 'n i Other and further objects of my inventionwill be understood from the specication hereinafter following byreference to the accompanying drawings in which:

`Figure 1 diagrammatically shows the fundamental circuits oi atransmitter arranged accordassumes in turn two values which are inopposition; Fig. 2 shows a curve representing the os- (Cl. Z-8)cillationsof ordinary telephony employing a carrier wave; Fig. 3 isacurve showing the oscillations in telephony without carrier wave; 4 is acurve showing the oscillations of an ordinary telegraph signal; Fig. 5indicates the detected 60 current furnished by the telegraph signal tothe recording relay; Fig. 6 is a curve Ashowing the oscillations of atelegraph signal in which the dots or dashes, on the one hand, and thespaces between the dots and dashes of the alphabet, on

, is furnished by the telegraph signal to the recording relay, when thereception takes place in accordance with my invention; Fig. 8 shows aschematic circuit arrangement for a receiving station employing a'localcurrentsynchronized with the incoming signal whose amplitude is alwayspositive, that is, whose phase is constant to 7 5 `which circuit thesystem o1' my invention may be applied; Fig. 9 illustrates a receivingcircuit arrangement responsive to signals whose phase assumes two valuesin opposition in accordance with my invention; Fig. 10 shows a modiedform 8O of the receiving circuit of my invention in which a harmonic ofthe local generator is utilized for coaction with the incoming signalingenergy; -g' Fig. 11 shows a curve explanatory` of the'receiving circuitsshown in Figs. 8 and 9; and Fig. 12 85 shows a complete receiving systemconstructed in accordance with my invention.

It is a known fact that in the receiving systems in present use, it isrequired that the amplitude of the oscillation forming the signal shallalways have the same sign. For instance, a telephonie transmission isrepresented by the algebraic expression [a-l-f (0] sin (wf+) and thegreatest care is takentha't the constant amplitude a of the carrier waveshall be at all times greater than the amplitude f (t) of themodulationfwhich is in turn positive and nega.- tive. l'

Inconsequence, the total amplitude "dfi-[(0 is always positive. ..0ntheother hand, its mean value during a prolonged space ot time is notnull,105 and it is in fact equal to a. f

In like manner, in ordinary telegraphy by full current or no current,the amplitude a of the oscillation maintains a constant value of +Sduring thev dots and dashes, and a zero value in the110 uuihniasionland,reception of spaces between the dots or dashes;` at no time willthis amplitude change its sign, and its mean value during a prolongedspace of time, or about is not null.v 1 l Instead` of these signalsgenerally used,` it is preferable to employ others in which theamplitude isf positive or negative in turn and will have a value whichis practically null.

'nus for example the case with the telephony without as shown by. theexpression. f fw. in @we in which the amplitude s=f(t), which isinturnpositive or negative', has` a meanV value which is null. or

,1,-;.1.r 4 i .-L I().d`t =0 j Y This will also be the case (which hasnever as yet been considered) for a telegraphic transmission in whichthedots and dashes-of theA alphabet are formedbyan-oscillation'- a andthe spaces between dots and dashes, by an oscillation is ,in (whack-+Ssin (cH-s-l-f) In this case` as well, since the Vamplitude s has thevalues +S and -S in turn, its mean value I on. dt during a prolongedspace of time would very small. Such signals could not be received by anordibe hun or nary receiver, and would not be intelligible in atelephone asthey would be reproduced as acontinuous tone. However,theoretically, the signals could be recorded if the receivingstationcontained a local'generator providing a current by which thesignal would the modulation of a current s. siniwH-p) by another currentH sin (wot-l-qso) furnishes, among others, a resultingcurrentproportional to the use of a local current-complying with the conditionwould finally produce a current s=f (t) in the recording apparatus whichreproduces the modulation.

For the reasons `above stated, this `result could not be heretoforeobtained by existing systems or methods and my invention accomplishesresults not heretofore obtainable.

Referring to the drawings in detail, the transmitter may consist of atelephony station which is so'arranged as to eliminate the carrier waveor current. A telegraphy station as shown in Fig.

l may also be employed. The transmitter consists of an oscillator l-andampliers 2 and 6 connected therewith. A coupling transformer ,disposedbetween the output of amplifier tube 2 and the input of tube 6, whichtransformer includes a secondary winding includinghalf sections 3 and 4.The two -halves of, the transformer winding 3-4 produce electromotiveforces which are the be stated as follows.

i latter by, fullcurrent or no current,

`be modulated. Since reverse of one another, are put in use alternatelyby keys 5 operative between contacts connected with opposite ends ofwinding 3-4, and supply to the antenna or to the transmission line 7through amplifier 6 the currents or oscillations of the masteroscillator 1. According to the posiition of thekeys 5, the antenna ortheline 'l will transmit, as desired, a current v.

+S; sin (tgt-+4 or a current -S. sin (ut-Hb) In the receiver, thephenomena linvolved may plitude s of an oscillation is in turn positiveor negative, is a simple mathematical expression connected with theconventional definition which is given to the amplitude, but in reality,this expression signifies thatthe phase of: the received oscillation isin turn equal to orfto +i. This actual condition is shown by thefigures. In Figs.

2 and 4, relating to ordinary transmission, the

former with a modulated carrier wave, and the the phase of theoscillation remains constant. 0n the contrary, in Figs. 3` and 6 whereofone relates to telephonie transmission without carrier wave, and

the other to telegraphic transmission employing The statement that theaminturn two oscillations whose amplitudesare +S and -S, the phase isreversedat the moments 8, 9

. 10,11, 12'and 13. e

For this reason. it is no longer possible, properly speaking, tosynchronize a local generator with these signals, as the object of thisgenerator is to supply ra currentH. sin (wt-ke) whose pulsation w andphase are constant, while the phaseof the signal is variable.

In particular, the method described in my copending application SerialNo. 574,858 filed November 13, 1931, and'entitled Synchronization systemis no longer applicable. The said arrangement, which serves for ordinarysignals as shownin Figs. 2 and 4, consists essentially as can beunderstood more clearly from Fig. 8 in modulating the received signal s,at v14: by the current H. sin (wbt-M0) of a local generator 15;the'modulation being effected in a at 17, it furnishes a low-frequencycurrent.

s. cos [(wo-w) +0- the meanV value of the synchronizing current s. cos(rpo-qs) would be evidently null, and thc control 'would not bepossible. For the reception of signals without carrier waves, thereceiving circuit shown in Fig. 3 must be rearranged. a The featurewhich characterizes my present lnvention consists in controlling thefrequency of the local generator, no longer by using for this u purposethe variable-phase periodic current constituting the signal, but bytransforming this current by suitable means and producing, from thistransformation. an auxiliary current having a constant phase. Numerousmeans are already known for obtaining, from a periodic cursin (wt-Hz)collected detecting valve 16, and aftera filtering operation;

rent, whose phase is alternately and +1r, another current whereof oneor-more harmonics have a constant phase.

The signal may, for instance, be sent into a -detector having the effectof the square; signal supplies to the detector an oscillationrepresented in turn byA S. sin (cH-4:) or by S. sin (wt+ +f), and it istransformed therein into a constant current represented by of two, orall of the consecutive alternationsof a sinusoidal current, all of theeven-.numbered harmonics have a phase which is independent of thephasereversals to which this sinusoidal current may be subjected. Forinstance, lth'evalve's l 19-20 (Figs. 9 and 12) will be used"',onieither side of the' sharp bend 28 V(Fig. 11),whifch is formed in theirplate circuitl characteristic curves; by inserting resistances 21-422intogtheirgrid Circuits. i.

n is aiso of a transformer in which the'iron-is operated` near thesaturation point. r

When once in possession, by suitable means, of

a current resulting from the signal, but whose phase is constant and isindependent of the phase-reversals of this signal, it is now possible tocontrol the frequency of the local generator. I may for example make useofthe arrangement shown in Fig. 8, modifyingv it as follows:` thelow-frequency current orpotential which becomes continuous atsynchronism and serves to control the frequency of the local generator,isob- .tained by the mutual modulation, not ofthe signalreceived in thereceiver and the oscillation of the local generator, but of twoauxiliary oscillations which are currents of double frequency, Yobtainedby sending each of these oscillations through a rectifier.`

Fig. 9 shows a circuit arrangement for the re` main invariable inrelation to one of the phases (wt-Hb) for instance, of thesignaloscillation.

This result evidently, cannot be obtained directly, but the object ofthe invention is, pre'- cisely, to surmount the diiiiculty by doublingthe frequencies. The frequency of the signal oscillation iS sin (wt-MJ)is doubled in 19, which produces in 25 a certain auxiliary oscillationS1 sin (Zat-i-Zc), whose phase is at present constant, and the amplitudepositive. In the same way, the frequency of the locally generatedoscillation Hsin (wat-M0) is doubled in 20, which proreasibie to' sendthe signalfoscnia#iw tion into a frequency-doubling deyicefconsistingsistance 18, and it produces at the end 32 of duces in 27a secondauxiliary oscillation H1 sin (2wot+2). Y. e

The two auxiliary oscillations, whose .phases are both independent ofVthe inversionsgof the signal oscillations, arevthus ordinaryoscillations thatmay be synchronized one with the other by simplyapplying the process already described in my copending applicationSerial No.y 574,858, filed November 13. 1931. These oscillationsinterfere inthe detector 16 and the resulting detected current controls,by means of. tap 32, conductor 33 and local generator 15, 34, the

frequency i 2r' I 1 of the auxiliary oscillation furnished to thedetector by transformer 27.1 It is not at` all necessary `thatthefrequency ofthe controlled generator 15, 34 be: equal to thefrequency`of the synchronized oscillations. The frequency of one of the` twosynchronized oscillationsshould depend onthe local generator whosefrequency is con- Vtrolled,l the modeof `dependence remainsv arbitrary;and it is'permissible to transform in any way,` the frequency o fYthellocally generated oscillation' between. generator. 15, 34 andtransforiner.27. ,Llfjk r .Y The device of Fig`.`9 realizes thus asynchronism betweenfthetwo auxiliary oscillations, and the saidsynchronism is all the more stable when the m5 twoj'oscillationsinterfering in the detector 16 1 are maintained. in quadrature whichproduces, when'lK` is an integer i `The phase wat+0 of the localgenerator 15, 3a 115 mains constant.

The osciuation of the signal s. sin (www or AS. sin (wt++1r) which iscollected at 14, actuates the grid'of a valve 19, through the medium ofthe resistance in series 21 adapted tobend the Vcurve of the platecircuit characteristic. Vl3y v125 reason of this bend,'there is producedin the f plate circuit a current of double frequencyand of constantphase. This current energizes thel filter 24 which is tuned tothe newpulsation 2o, and said lter energizes in turn, by means of 1 0 thetransformer 25, the grid of the detectingl valve 16. The detection maytake place by means'AE of a shunted condenser 304 or the likeconstitut-l ing a grid leak. Theoscillation H. sin (wot-Hoa) of thelocal generator 15, which is collected at 1 31, actuates the valve 20 inwhich is produced an auxiliary current having a pulsation 2mn. Thiscurrent is filtered at 26 and it also energizes the detecting valve 16by means ofthe transformer 27. These two auxiliary currents,

vwhose frequencies are respectively double the frequencies of the signalandof the local generator, are mutually modulated in the valve 16 whoseplate circuit becomes. among others, the seat of a current of very lowfrequency, proportional to After passing through the low pass-bandfilter 17, this current will alone pass through therethis resistancevariations of potential Vwhich are valso represented by theprecedingexpression.

These variations control, 'within very narrow limits, the properfrequency of the local generator it is possible for instance tosupplytheplate circuit of this generatorfrorn the tap connection'32, as it is aknown fact that bychanglng the plate circuit tension or ssen-excitedgenerator, its frequency is somewhat changed.

'Ihe synchronizing device shown in Fig. 9 is adiusted as follows: Theaction of the signalis reduced by loosening (for instance) the couplingof the transformer 62 until the beats of the pulsation 2bn-u) due to theinterference between the two auxiliary; currents -having respectivelythe pulsations 2o and2u are `faintly heard in the signal. This isobserved by the fact that the beats heardin the telephone 36 becomeslower in pitch and are then inaudible. The coupling 62 is then madec1oser.,so that the signalwlll assume its normal intensity.` -V The twoauxiliary currents which interfere `in the valve`l6 will ,then act uponthe proper frequency of the generator l5.d erived from the `tapconnection `32and the'connection 33, and will thus be automaticallysynchronized.

This is observed to take place when the pointer of the milliampere-meter35 remains stationary.

Ii'. as frequently happens, the local generator 15 willitself produceharmonics which are superposed upon its fundamental oscillation H sinfmt-tw). theyalve 20 which serves to produce the auxiliary `current ofpulsation 2q. now becomes superfluous; the simplified arrangement shownin Fig. 10 can hence be employed, and herein the local generatorY 15 isdirectly coupled to the filter 26 to isolate itsusecond harmonic. Theremainder of the arrangement -is the sameas the one already described;the two auxiliary currents which interfere in thevalve 16 in` which theybecome synchronized, will form respectively the second harmonic ofL thelocal generator, and the, current whose pulsation is 2u obtained fromthe signal by sending the latter through a valve having a sharp bend inits characteristic curve at 28,\and through the filter 24.

The arrangement for synchronizing the two auxiliary currents is setforth more fully in my copending application `hereinbefore referred to.

The synchronism isgmorestable `when the two oscillations which aremutually modulated in the valve ism-e 1n quadrature therein; theobtainment of this result can be observed by the fact that the currentin the milllampere-meter 35 is.-

not changed by the controlling. oscillation received at 14. g t f Pig,l2 shows areceiver embodying my invention. and herein the signals arereceived by the antenna orby the line 49; they areMselected andamplified at 50, and may be. modulated by a heterodyne 51 adapted toreduce their frequency. When issuing from this circuit, the wavesenergizewa valve 52 `whose plate circuit supplies through a transformer62 two circuits. The circuit at the upper part of the diagram in Fig. 12comprises `a valve 53 whose plate circuit acts. through a transformer54, upon the grid of a` detecting `valve 55 having the recordingapparatus 57 connected'with the output thereof. The

appar tus 57 may consist of a vtelephone or a relay. e other circuit atthe lower part of the figure represents the aforesaidsynchronialngarrangement shown in l The oscillation of the signal can also bemodulated at the transmitting station, and can be given the known form ln sri+sln nt+ 1sin t+ At the receiving station, the oscillations having`the pulsation can be selected and detected in order to obtain adetected current which is proportional to Y s. emot-to) The' receivingmethods hereinbefore set forth can then be employed for thepulsation il.

In Fig. `12, the phase displacing device 59. 60 allows the diiferenceof45 or 225V heretofore referred to, to be cancelled and finally.' the`oscillations acting on detector 55 which feedsthe register 57 are :ssimo-+o) for the signal;

.H sin( @+40 for the locally generated oscillation.

I have found the communication system of my l invention highly practicalfor transmission `andV reception without the carrier wave., My inventionis applicable to both line wire communication and spaced radio systems.While I have described my invention in certain preferred embodiments, I

desire that it be understood that modifications may be made and that nolimitations! my invention are intended other than are imposed by thescope of the appended claims.

What Iclaim as new and desire to secure by `LettersPiment of the Unitedstatesisas follows:

l. A receiving system adapted to receive a rsignal consisting of anoscillation whose frequency is constant and whosephase assumesalternately two values in opposition, comprising, a local generatorsupplying a continuous oscillation having the same frequency-as thesignal oscillation, `means for obtaining from the said signaloscillation a first auxiliary oscillation whose phase is constant andwhose frequency` is a multiple of `that of the signal oscillation, meansfor `obtaining from the continuous oscillation supplied by the localgenerator a second auxiliary oscillation having the same frequency asthe firstmentioned auxiliary oscillation, means for,ef fecting theinterference of the two auxiliarynos- `cillations for producing aresulting interference los current, means for controlling the frequencyof the saidilocal generator by the said interference current, and meansfor simultaneously impressing the signal oscillation and the continuousoscillation supplied by the local generator on the Y detector of thereceiving system. e

2. A receiving system adapted to receive a signal consisting of anoscillation whose frequency is constant and whose phase assumesalternately two values in opposition, comprising,` a local generatorsupplying a continuous oscillation of the same frequency as the signaloscillation, a first rectifier, whose input circuit is affected by thesignal oscillation and whose output circuit supplies rst auxiliaryoscillation `whose frequency is double that of the signal oscillation, asecond rectifier, whose input circuit is affected by the continuousoscillation ofthe localgenerator and whose output circuit supplies asecond auxiliary oscillation whose frequency is double that of the saidcontinuous oscillation, a third rectifier, which is simultaneouslyaffected by the said auxiliary oscillations and in which the twoauxiliary generator, and means for simultaneously impressing the signaloscillation-,and the continuous oscillation supplied by .thelocalgenerator on the'dete'ctorof the receiving system.

. 3. A receiving system adap'tedrto receive'a..sig nal consisting of anoscillation' Whose-,frequenyg is constant and whose phase as suminzturrrtwo values in oppositiomcoinpriszing whose frequency is amultiple '-ofthefsign quency, a'. second auxiliarycircuit fadapte oselect the harmonic of'the'localoscillationihaving` the same lfrequencyas the auxiliary oscillatiom a rectifier inxwhichftljieauxiliary'oscillatiornob-'Yl tained from the signal-and'jtnejharrnonicobtained from the 1ocal-oscillation-a're-- caused l,toxinterf` fere, aconnection by which the current produced by this interference controls'the frequency of the generator, and means for simultaneously irnpressingthe signal and the local oscillation supplied by the generator on thedetector of the receiving system. v

4. A receiivng system adapted to receive a signal without carrieroscillation, comprising: a. local generator supplying a continuousoscillation having the same frequency as the signal,

means for obtaining from the oscillation constituting the signal a firstauxiliary oscillation Whose phase is constant and Whose frequency is amultiple of that of the signal, means for ob- DISCLAIMER taining fromthe continuous oscillation supplied by the local generator a secondauxiliary oscillation having the same frequency as the rstmentionedauxiliaryv oscillation, means causing the interference ofthe twoauxiliary oscillations. means for controlling the frequency of the saidlocalgenerator by the current produced by the fsaid interference, andmeansfor simultaneously impressing the signal and the continuousoscillation-supplied by the local generator on the decotone; thereceiving system. l

A' receiving system adapted to receive a teleraphic signal in which thed ots and dashes on onev hand, and the spaces between the dots ndjdasheson the other hand, consist respective-s yof two oscillationshaving thesame frequency and in phase opposition, comprising: a localgenier-atorsupplying a continuous oscillation having :the same frequencyas the signal, means for obtaining from the oscillation constituting thesaid signal .a rst auxiliary oscillation whose phase is constant andWhose frequency is a multiple of that of the signal, means for obtainingfrom the continuous oscillation supplied by the local generator a secondauxiliary oscillation having the same frequency as the first-mentionedauxiliary oscillation, means causing the interference of the twoauxiliary oscillations, means for controlling the frequency of the saidlocal generator by the current produced by the said interference, andmeans for simultaneously impressing the signal and the continuousoscillation supplied by the local generator on the detector of thereceiving system.

HENRI JEAN JOSEPH MARIE DE'REGNAULD DE BEILESCIZE.

1,922,282.-Hem Jean Joseph Marie de Regnaiild de Bellescize,vl\leuillysur-Seine France. SIGNAL RECEIVING SYSTEM. Patent dated Augustl5, 1933. Dis claimer led June 9, 1937, by the patentee.

[ cic Gazette July 6, 1937.]

DISCLAIMER l,922,282.ienri Jean Joseph Marie de Regnauld de Bcllesct'ze,Neuilly-sur-Seine l rance. SIGNAL RECEIVING SYSTEM. Patent dated Augustl5 1933 Dis claimer filed June 9, 1937, by the patentee. o

Hereby enters this disclaimer to claims 1 and 3 of said Letters Patentas follows:

l 4 t, L r 1. lo any local gommate] supplying a continuous oscillationhaving the same frequency :is the signal oscillation, as set forth inclaim l, except as the said same frequency .is obtained throughadjustable tuning means actingr upon the freqiiency 'relation ol the twooscillations, whereby the phase relation of the synchronized Waves uni-yhe brought to quiuli'ature.

lo .any inerutcr supplying a local oscillation having the same frequencyas the signal" oscillatifui, as set forth in claim 3, except as the saidsaine froquenc is obtained through zuljustuble tuningnieans acting uponthe frequency rcli'tioh of thor; sind oscillations; to any connection bywhich the current produced by this intericnncn controls the frequency ofthe generator, exi-,opt as the said connection isa purely electrical onewhereby the said frequency control is speedy enough to follow theaccnlouiul .frefniein-- und phase fluctuations of the signal oscillatioiThis disclaimer cori'utin' I u error as to claims l and 3 su ersedesdisclaimer n m V ub lished in O` fu. July o, 193i. p p

y Dis'oLAlMl-:R i 1,922,282.Hem-i Jean Joseph Marie de Regnauld deBellescz'ze, Neuilly-sur-Seine,

France. SIGNAL RECEIVING SYSTEM.v Patent dated August 1.5, 1933.Disclairner filed June 9, 1937, by the patentee. Hereby enters thisdisclaimer to claims 1 and 3 of said Letters Patent as follows:

1. To any "local generator supplying a continuous oscillation having thesame frequency as the signal oscillation, as set forth in claim 1,except as the said same frequency is obtained through adjustable tuningmeans acting upon the frequency relation of the two oscillations,whereby the phase relation of the synchronized waves may be brought toquadrature. l

3. To any generator supplying a local oscillation having the samefrequency as the signal oscillation, as set forth in claim 3, except asthe said same frequency is obtained through adjustable tuning meansacting upon the frequency relation of the said oscillations; to vanyconnection by which the current produced by this interference controlsthe frequency of the generator, except as the said connection is a.purely electrical one whereby thesaid frequency control is speedyenough to follow the accidental frequency and phase fluctuations ofthesignal oscillation.

This disclaimer correcting errorl as toA claims 1 and 3 supersedesdisclaimer published in O. G. July 6, 1937. v

